With one hearing aid device, an input signal is recorded by means of an input converter and is converted into an electrical input signal. Typically, at least one microphone which records an acoustic input signal serves as an input converter. Modern hearing aid devices frequently comprise a microphone system with a number of microphones, in order to achieve a reception which is dependent on the direction of incidence of acoustic signals, a directional characteristic.
The input converters can however also have a telephone coil or an antenna in order to record electromagnetic input signals. The input signals converted into electrical signals (audio signals) by means of the input converter are fed to a signal processing unit for further processing and amplification. The further processing and amplification is generally carried out as a function of the signal frequency in order to compensate for the individual hearing loss of a hearing aid device wearer. The signal processing unit generates an electrical output signal, which is fed to the ear of the hearing aid device wearer by means of an output converter, so that said hearing aid device wearer perceives the output signal as an acoustic signal. Receivers which generate an acoustic output signal are typically used as output converters. Nevertheless, output converters for generating mechanical vibrations are also known, which directly stimulate certain parts of the ear to vibrate, such as the ossicles for instance. Furthermore, output converters are known, which directly stimulate nerve cells in the ear.
As a result of the miniaturization sought in hearing aid devices, the microphone and the receiver of a hearing aid device are generally only distanced minimally from one another. This promotes an unwanted sound transmission directly from the receiver to the microphone, thereby frequently resulting in disturbing feedback whistling (feedback). A plurality of different approaches exist for solving this problem, such as the use of notch filters, adaptive filters, directional microphones or an extensive sealing of the auditory canal. None of these measures has however previously been able to reliably and completely eliminate the occurrence of feedback-related whistling.
U.S. Pat. No. 5,757,932 discloses a hearing aid device system with a hearing aid device which can be worn on the left ear and a hearing aid device on the right ear of a user. Audio signals are transmitted between the hearing aid devices. Signals, which represent acoustic signals recorded on both ears, are thus processed in both hearing aid devices. In this way, a binaural output signal can be fed to both ears of the user.
EP 941014 A2 discloses a hearing device system, in which hearing device system a control signal is transmitted from one hearing device to a second hearing device.
DE 10048354 A1 discloses a hearing device system having two hearing devices, in which acoustic field characteristics are generated in each hearing device and are transmitted to the respective other hearing device.
WO 00/00001 A2 discloses a hearing device system with two hearing devices, in which the signal processing in the two hearing devices is synchronized between the hearing devices by means of a wireless connection.
A method for communicating between hearing devices is known from DE 10304648 B3, in which data packets of a higher priority are first transmitted.
EP 0 941 014 A2 discloses a hearing aid device system with two hearing aid devices which can be worn on the head for the binaural supply of a user. The hearing aid devices comprise means for the wireless transmission of control signals and audio signals between the hearing aid devices. This allows the audio signals obtained in the two hearing aid devices by means of the microphone to be at least partially processed in only one of the two hearing aid devices. Resources for signal processing must thus not be similarly provided in both hearing aid devices.
The known hearing aid devices are disadvantageous in that the feedback problem has previously only been unsatisfactorily solved.